The primary objective of the Radiological Physics Center (RPC) is to assure NCI and the cooperative clinical trial groups that participating institutions have adequate quality assurance (QA) procedures and no major systematic dosimetry discrepancies, so they can be expected to deliver radiation treatments that are clinically comparable to other institutions in the cooperative group. In order to accomplish this objective, the RPC monitors the basic treatment unit output and brachytherapy source strength, the dosimetry data used by the institution, the calculation algorithms used in treatment planning, and QA procedures. The methods of monitoring include on-site dosimetry review visits and various remote audit tools. During on-site reviews, key personnel are interviewed, physical measurements are made on therapy machines, dosimetry and QA data are reviewed, treatment planning algorithms are tested and patient dose calculations are evaluated. The remote audit tools include: 1) mailed TLD evaluated on a periodic basis to verify output calibration;2) comparison of dosimetry data with RPC """"""""standard"""""""" data to verify comparability of the dosimetry data;3) evaluation of reference and/or actual patient calculations to verify the treatment planning algorithms;4) review of an institution's written QA procedures and records;and 5) mailed anthropomorphic phantoms to verify tumor dose delivery for special treatment techniques. The RPC continuously modifies its techniques to reflect new protocols and changes in practice at participating institutions. The RPC currently monitors 1338 radiation therapy facilities. Any discrepancies found by the RPC are pursued to help the institution resolve them. Thus, the RPC's overall QA program impacts not only on clinical trial patients, but on the quality of all patients treated at the institution.

Public Health Relevance

The RPC serves as a resource in radiation dosimetry and physics to the radiotherapy community and to the cooperative groups and collaborates with the 4 radiotherapy QA offices. The RPC provides advice to the cooperative groups on QA questions, and on the development of the radiotherapy section of protocols. The RPC continues to research dosimetry questions related to the use of a wide variety of therapy equipment to deliver clinically comparable treatments.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Cooperative Clinical Research--Cooperative Agreements (U10)
Project #
Application #
Study Section
Subcommittee G - Education (NCI)
Program Officer
Deye, James
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Texas MD Anderson Cancer Center
Other Domestic Higher Education
United States
Zip Code
Kerns, James R; Stingo, Francesco; Followill, David S et al. (2017) Treatment Planning System Calculation Errors Are Present in Most Imaging and Radiation Oncology Core-Houston Phantom Failures. Int J Radiat Oncol Biol Phys 98:1197-1203
Kry, Stephen F; Dromgoole, Lainy; Alvarez, Paola et al. (2017) Radiation Therapy Deficiencies Identified During On-Site Dosimetry Visits by the Imaging and Radiation Oncology Core Houston Quality Assurance Center. Int J Radiat Oncol Biol Phys 99:1094-1100
Faught, Austin M; Davidson, Scott E; Fontenot, Jonas et al. (2017) Development of a Monte Carlo multiple source model for inclusion in a dose calculation auditing tool. Med Phys 44:4943-4951
Taylor, Paige A; Kry, Stephen F; Followill, David S (2017) Pencil Beam Algorithms Are Unsuitable for Proton Dose Calculations in Lung. Int J Radiat Oncol Biol Phys 99:750-756
Huang, Jessie Y; Followill, David S; Howell, Rebecca M et al. (2016) Approaches to reducing photon dose calculation errors near metal implants. Med Phys 43:5117
Taylor, Paige A; Kry, Stephen F; Alvarez, Paola et al. (2016) Results From the Imaging and Radiation Oncology Core Houston's Anthropomorphic Phantoms Used for Proton Therapy Clinical Trial Credentialing. Int J Radiat Oncol Biol Phys 95:242-8
Davidson, Scott E; Cui, Jing; Kry, Stephen et al. (2016) Modification and validation of an analytical source model for external beam radiotherapy Monte Carlo dose calculations. Med Phys 43:4842
Scarboro, Sarah B; Cody, Dianna; Alvarez, Paola et al. (2015) Characterization of the nanoDot OSLD dosimeter in CT. Med Phys 42:1797-807
Huang, Jessie Y; Kerns, James R; Nute, Jessica L et al. (2015) An evaluation of three commercially available metal artifact reduction methods for CT imaging. Phys Med Biol 60:1047-67
Gibbons, John P; Antolak, John A; Followill, David S et al. (2014) Monitor unit calculations for external photon and electron beams: Report of the AAPM Therapy Physics Committee Task Group No. 71. Med Phys 41:031501

Showing the most recent 10 out of 78 publications